Design This was a non-blinded multiple-site randomised controlled clinical trial.Case selection Children, aged 5-6 years, were recruited from 11 government-funded kindergartens (pre-schools) in Selangor, Malaysia. The kindergartens were randomly allocated to either the Intervention Group (n = 185 children) or the Control Group (n = 142 children). A clinical examination was conducted to determine the participants' baseline caries experience. Over a 24-month period (commencing in 2015), the Intervention Group received six -monthly dental home visits (DHVs) to provide the families with oral hygiene and dietary instruction, along with educational leaflets. The Control Group received only the educational leaflets. Caries incidence was measured in terms of both the proportion of children who developed new carious lesions, and the number of primary molars in which new carious lesions were seen at 24 months.Data analysis A chi-squared test was used to compare baseline socioeconomic characteristics as well as the proportion of children in each arm who developed new carious lesions. A t-test was used to compare the mean number of primary molars that developed new caries in each group. In addition, the number needed to treat (NNT) was determined.Results There was a 70% (n = 132) and 71% (n = 100) completion rate for participants in the Intervention and Control Groups, respectively. At 24 months, the key finding was that significantly fewer children in the Intervention Group (14.4%; n = 19) had developed new caries lesions compared to the Control Group (60%; n = 60) (p = 0.001). The NNT was calculated as 2.2, to prevent new caries in one child. After controlling for parental education level and household crowding, children in the Control Group were 8.2 times more likely to develop caries in their primary molars than those in the Intervention Group.Conclusions The authors concluded that in a middle-income country such as Malaysia, six -monthly dental home visits are an effective caries prevention strategy for children aged 5-6 years old from low-income families.